1. Field
One or more embodiments described herein relate to a battery.
2. Description of the Related Art
A rechargeable battery is one that is repeatedly charged and discharged. A low-capacity rechargeable battery is often used in small portable electronic devices, e.g., mobile phones, notebook computers, and camcorders. A high-capacity rechargeable battery is often used in hybrid or electric vehicles or large-capacity power storage devices.
High-capacity rechargeable batteries include one or more battery modules, each equipped with multiple rechargeable batteries connected in series. The batteries are enclosed within a case that is either electrically neutral or has an electrical (i.e., positive or negative) polarity. Unlike a battery with an electrically neutral case, a battery having a positively charged case is safe against short circuits caused by penetration of external foreign objects (e.g., nails). Also, the existence of a voltage abnormality of a battery having a case with an electrical polarity can be easily checked.
In order to configure a battery module with a case having an electrical polarity, insulation may be used. This insulation increases production costs. Therefore, it is cost effective to use rechargeable batteries that are electrically neutral.
However, because a battery with an electrically neutral case is unstable compared to a battery with a case having an electrical polarity, the existence of a voltage abnormality of a battery with an electrically neutral case cannot be easily checked.